It's a disturbing thing any time you feel a lump in the anal region, but it's important to find out exactly what that lump is so that you can treat it correctly. It would be truly silly to go through all the trouble to treat a hemorrhoid when all you've got is a blister. While blisters aren't exactly common in the anal region, there are a couple of different ways they can occur. Fortunately, it's also easy to tell the difference once you know what you're looking at.
Skin is composed of three layers, the epidermis, the dermis, and the subcutis in order of depth. Blisters are small pockets of clear fluid that form between the epidermis and the dermis when something forces the two layers apart. This fluid, called plasma or serum, is a derivative of blood that helps in healing, and it collects to protect the deeper tissues from further damage. Of course, blood blisters and pus blisters are also possible, but the fluid in question will be either red or yellowish and opaque, respectively. Blisters are usually caused by friction, burning, freezing, chemical exposure, or infection. Any blister that coule be confused with a hemorrhoid will not likely be caused by burning or freezing, but any other cause is quite possible.
While it may not be the easiest thing in the world to diagnose a lump you can't see, there are a few key points that you can use to figure out whether you're looking at a blister or a hemorrhoid. First off, blisters are thin membraned and on the surface of the skin, while hemorrhoids originate from far below the skin. Naturally, this makes the lump feel quite different. Second, while hemorrhoids can be as small as a pea, blisters often don't get much larger than one. So, if the lump feels like it has a thin membrane and is only on the surface of the skin instead of beneath it, odds are you've got a blister instead of a hemorrhoid.
One of the reasons that figuring out whether you're suffering from a blister or a hemorrhoid is so important is because the causes and preventions for the two are very different. Hemorrhoid causes and prevention are covered quite exhaustively elsewhere on this site, so we won't go over it again. However, the causes and prevention for blisters in the hemorrhoid area are worth noting.
Friction blisters are by far the most common variety of blister to suffer from anywhere on the body. The basic idea is that forceful rubbing from some source causes enough shear forces within the skin to cause separation and filling. Naturally, there are a couple of possible sources this may come from in the hemorrhoidal area. Excessive cleaning, overly tight clothing, or excessive weight can all cause friction in the hemorrhoidal area that can lead to blisters, and each of these causes should be carefully examined and eliminated if possible.
Friction blisters are most common on moist, warm skin. Skin that's heading towards extremes, such as excessively wet or dry or hot or cold, doesn't blister as easily or readily as skin that's just moist and warm. Obviously, this spells trouble for the area one most commonly finds hemorrhoids.
To prevent friction blisters, first try to wear soft cotton briefs and avoid rubbing at the area to clean. Pat the area gently with soft, moist cloths for hygiene, and never scrub at it. Weight loss may be a long term goal, but it probably won't help in the immediate, so try to eliminate everything else first. In addition, you can use talcum powder in the area to dry and lubricate enough to avoid blisters. However, it's important when using talcum powder to avoid build-up and caking which can make the problem worse, so make sure you keep up with the moist wipes and the gentle patting.
The skin covering your hemorrhoidal veins can also blister if it comes into contact with cosmetics, detergents, solvents, or any other chemical. This is commonly known as contact dermatitis, which is a fancy way of saying skin irritation due to contact with something. Yes, sometimes medical jargon just knocks itself out with originality, but it does serve a purpose. Contact dermatitis may also happen due to an allergic reaction, usually involving insect bites or stings. This type of blister in the hemorrhoidal area can take a bit to figure out, because you're going to have to find the common denominator for when the blisters appear and then eliminating it. Changing brands of laundry detergent or toilet paper can sometimes help. If it's due to something like your laundry detergent, it's quite possible to get contact dermatitis in the hemorrhoidal area without getting it all over your body because the skin around the anal sphincter is thinner and more sensitive than a lot of the skin on your body.
Blisters that arise due to infection are quite rare in the hemorrhoidal area because the skin cleans itself under normal circumstances. However, there are rare occasions when a microbe can get a foothold and cause issues. Normal hygiene should prevent these entirely, but if an infected blister should try to masquerade as a hemorrhoid, you must be very careful to uphold all of the treatment standards for a blister. If it should pop, then you probably want to at least see a doctor to make sure that the infection does spread further on your skin or to other areas.
The biggest thing about treating any blister is to keep it intact if at all possible. Some blisters are very fragile indeed, so this can be difficult. However, should you already have a blister in the hemorrhoids area, it's even more important to not scrub at it. If you can keep the blister from popping, then you need not do much further to treat it. However, if the blister in the hemorrhoidal area does pop, then you should probably take further steps. Clean it gently with witch hazel extract and regularly apply a triple antibiotic ointment to make sure that healing goes as quickly as possible and that infection gets no chance to set in.
Hanna T, Carlson JM. "Freedom from Friction," OrthoKinetic Review. Mar/Apr 2004;4(2):34-35.
Uchinuma, E; Koganei, Y; Shioya, N; Yoshizato, K (1988). "Biological evaluation of burn blister fluid". Annals of plastic surgery 20 (3): 225–30.
Taber's Cyclopedic Medical Dictionary, 2005
AUTHOR: Loni Ice.